Please, do NOT force your toddler to hold the pencil the way a school child does, with 3 fingers on the pencil â you may do more harm than good. It is very hard to âunlearnâ a poor pencil grip later in life! Each stage of holding a pencil or crayon is dependent on how âsteadyâ the shoulder and arm muscles are.
In the equation of a straight line (when the equation is written as  y = mx + b ), the slope is the number  m  that is multiplied on the x, and  b  is the y-intercept, where the line crosses the y-axis.
That's why slope of a horizontal line is 0. You can also think of this mathematically. Slope represents how many units the line goes up for every unit it moves to the right. This line doesn't go up at all, so it goes up 0 units for every 1 unit of movement to the right. That makes the slope 0/1, or 0.